Munich Re said in a statement Tuesday that Buffett's share of the voting rights amounted to 10.24 percent on Oct. 12.

The company said Buffett had told it that "the investment serves the purpose of making trading profits and not of implementing strategic objectives." It added he intends to acquire further voting rights over the next year.

Munich Re announced in January that Omaha-based Buffett, who invests through his company Berkshire Hathaway Inc., held just over 3 percent of the company, and the investor has increased his stake since then.

The company's shares were up 1 percent at euro108.30 ($150.80) in Frankfurt trading.